This invention relates to a biochemical analysis apparatus for chemically analyzing and measuring the characteristics of a body fluid, particularly blood, by using a test piece having a layer containing a reagent, and more particularly to the improvement of an apparatus for applying a sample to each reagent layer of a multi-item test piece or to each reagent layer of several single item test pieces set on a test piece table.
For biochemically analyzing blood (plasma, serum, whole blood) for the presence, quantity, and change of special components, a wet system using liquid reagents is available and also a dry system using solid phase reagents is available. In the latter system, a test piece is used wherein filter paper or a film is impregnated or coated with a reagent. Such a test piece is readily utilized in combination with a conventional apparatus including a reflectometer, and such test pieces have been generally used as a bedside test for an inpatient or as an instantaneous real time test for an outpatient.
Measurement technology has made substantial progress along with the progress in reagent and analysis instrumentation. By combination of the information in a single item measurement, such as glucose concentration and multi-components, a general diagnosis has been made of various diseases or organ disorders and in effect an evaluation of health has been synthesized to assist in treatment.
For example, by a set of tests of GOT, GPT, ALP, LAP, .gamma.-GPT, and BUN in blood, a diagnosis of liver disorders is achieved. To assess the health of a patient in a first examination, blood sugar, creatinine, uric acid, BUN, cholesterol, TP, amylase, LDH, and GOT, are analyzed as a profile test. Additionally, there are several combinatorial analyses for the diagnosis of renal function or diabetes.
To conduct these combinatorial analyses in a short time, concurrent reactions and measurements of a number of items are necessary. Also, in a situation where a single item measurement is to be made on a multitude of samples, concurrent multimeasurement improves efficiency.
However, in the case of blood analysis, the applied sample quantity is extremely small, and by delaying evaluation after applying the sample to a test piece, a higher concentration tends to appear as the measured value because of water evaporation from the sample. Particularly, since the reaction proceeds at a relatively higher temperature (about 37.degree. C.), evaporation is accelerated. Further, during a delay in making an evaluation, fluctuations in reaction temperature tend to occur.
To solve the above problems, for example, the table for holding a test piece has been made slidable into a photometric apparatus with a close fit. Also, a small closed space is provided. Immediately after applying the sample, the test piece is moved to the closed space. However, a moving mechanism for an individual test piece, that is, a single item test piece with a reagent layer, is extremely complex. Further, when an apparatus for evaluating a multi-item test piece with plural reagent layers using several of the same or different types, is used, which evaluates samples concurrently by plural measurement means, movement of an individual reagent layer test piece into the closed space is impossible.